According to the Luxury watch blog A timepiece indicating only hours, minutes, and seconds is otherwise
known as a simple movement. Common additions such as day/date displays,
chronographs and automatic winding mechanisms are usually not
sufficient to permit a movement to be called complicated. Moreover,
that a watch movement may be a Certified Chronometer does not itself
count as a complication.
The more complications in a watch, the more difficult it is to
design, create, assemble and repair....
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